The group released a 153-page report, "All You Can Do is Pray: Crimes Against Humanity and Ethnic Cleansing of Rohingya Muslims in Burma's Arakan State" describing the forcible removal of more than 125,000 Rohingya Muslims from Arakan state in Myanmar, formerly known as Burma.
The report said local Arakan state officials are responsible for the acts and that security forces have stood by or participated.
"The Burmese government engaged in a campaign of ethnic cleansing against the Rohingya that continues today through the denial of aid and restrictions on movement," said Phil Robertson, Human Rights Watch deputy Asia director. "The government needs to put an immediate stop to the abuses and hold the perpetrators accountable or it will be responsible for further violence against ethnic and religious minorities in the country."
The coordinated attacks against Muslim neighborhoods began in June 2012 after sectarian violence between Arakanese and Rohingya, the report said.
Since then the Arakanese have razed Muslim villages, killing residents and burying some in mass graves, and in one instance about 70 Rohingya people were killed, including 28 children who were hacked to death, the report said.